Manufacture of aldehydes



Patented May 16, 1933 UNITED STATES ADOLF JOHANNSEN, or LUnwIesHArEu-o mnn-RHmE..GEB ANY; assreiwoaf'ro GENERAL ANILINE wonxs, 1110., or imw'xonx, n; 1Y4 a CORPORATION or; Dana- WARE MANUFACTURE oranimninnsf I No Drawing. Application filed March 17, 1927, Serial 1Tb. 118,253fa1id-1n Germany Iarch 19, 1926.3

I have found that aldehydes can be prepared in a simple manner from carboxylic acids by acting on the latter at elevated temperatures and in the presence of catalysts with carbon monoxid. In this way for example benzaldehyde can readily be prepared from benzoic acid and acetaldehyde from acetic acid.

As catalysts especially suitable for this reaction the elements suitable for use as hydrogenating catalysts or mixtures of such elements may be mentioned. These catalysts may be activated by an addition of other elements or their compounds. As examples of very suitable contact masses which may be employed with good result, the elements of the 5th to 11th group of the periodic system (as suggested by Paneth, Zeitschrift fiir ange- Wandte Chemie, 1923, volume 36, page 409 Tab. 2) for instance, chromium, iron, copper, manganese, and cobalt or their oxids, either alone or in mixture with each other, may be mentioned. These catalysts give particularly good results when employed in mixture with other elements, for example lead, glucinum, cerium, uranium, or zinc, or oxids of these elements which will be referred to as activating substances.

The temperatures to be employed may vary within rather wide limits. The most suitable temperatures will generally range between about 200 to 550 0. preferably 250 to 500 C. The reaction may be carried out under any desired pressure.

The proportions of carboxylic acid and carbon monoxid need not be in the ratio theoretically required, but may be varied Within wide limits. The materials not consumed in the reaction may again be introduced into the process in a circulatory system. Inert gases or vapors may be present in addition to carbon monoxid.

The following examples will further illustrate how my invention may be carried out in practice, but the invention is not limited to these examples.

Example 1 monoxid in an amount suflicient for the reduction dand the mixture passed at 400"G;

over an iron catalyst' Benzaldehyde is obtainedina good yield. 1 I

i 0 Example a "a etic acid vapor ispassed together with carbommonoxid over a catalyst-consisting of cobalt and iron andfh eatedto 280 C; Aoetaldehyde is produced and canbe recovered from the reaction mixture by cooling-or A gas mixture "consisting; of. equal by'violume, of carbon monoxid and nitrogen lspassediover benzoic acidheatedto 1 remiltmg gas and vapor mixture ds passed at 360$ to 390 G. over a cataly stpre pared by reducing an intimate mixture of the. reactionzgases'henzaldehyde is sep'ara aiongwithnnalteredbenzoic ma:- 1 Producer gas or blast. furnace gas may'al'so be employed instead of the said'gas mixmre.

- s A gas mixture .consisting, by volume, "of 60 per centof carbon "monoxiid, 7 cent of n trrfen and .10 percentiof water vapor 1s mixe at to 4200 G; over a catalyst; containing cerium, chromium. and iron. Benzaldehy-de together with: some unaltened benzoic acid and benzene can be separated fromthe re actionxgases suitable manner. 1 V Then i anama in tlae saidgas mix ture mayl be replaced. 'whollylor in partby carbon-dioxide. Y Other canboxylic acids can be converted into aldehyde sin a similar'manner. j E

I claims I w- ;1 process of producing aldehydes with benzoic acid vapor andlpa'ssed which-comprises acting carbon monoxide on acaa'boxylic acid. at a temperature between about'200? to550 (5-. andinyfihe presence of .w hydroge mzting catalyst" comprising at lenstone element selected from the 5th to the 13th; gmup of-the Baneth-periodic-system;

2. The process of producing aldehydes' which acting carbon monoxide on a carboxylic acid at a temperature ranging between about 200 to 550 C. and in the presence of a hydrogenatingcatalyst comprising at least one element selected from the 5th to the 11th group of the Paneth peri odic system, and anactivating'substance selected from "the group consisting of lead, glucinum, cerium, uranium, zinc, and oxids of these elements. v V

3. The/process of producing aldehydes which comprises acting gases containing carbon monoxide on a carboxylic acid at a temperature ranging between about 200 to 500 C. and inthepresence of a hydrogenating 1 catalyst comprising at least one element selected from the 5thgto. the 11th group of the Paneth periodic system. I

4. The process of producing aldehydes which comprises acting carbon monoxide on 2 a carboxylic acid at a temperature ranging between about 200. and 550 C. in the presenceof a hydrogenating catalyst comprising at least one of the metals selected from the group consisting of-chromium, iron, copper,

manganese andcobalt. V l v 5. The process of producing aldehydes which comprises acting gases containing carbon monoxid on a carboxylic acid at a temperature ranging between-about 200 to 550 (l, .and intlie presence of a hydrogenating 'catalystcomprising. two metals selected from the group consisting ofchromium, iron, copper, manganeseand cobalt.

V .6. The process of producing aldehydes which comprises acting gases containingcarbon monoxid ona carboxylic acid at a temperature rangingbetween about: 200 to550 C'- and, in the presence of a hydrogenating catalyst comprising .chromium. I r

40 7. The process ofproducing benzaldehyde 1 which comprises acting'gases containing carbon monoxid on benzoic .acid at .a. temperature between. about360 and 400. C. in the presence of a hydrogenating catalyst comprising chromium andviron. H a 8. The process of producing aldehydes which comprises ac-tin gases. containing carbon monoxide ona .car oxylic. acida temperature ranging between 200 and 500 C. and

in the presence of-a hydrogenating catalyst comprisingat least one of .the metals selected from the group consisting of chromium, iron, copper, manganese and cobalt, and an actiyating substance selected from the group consisting of lead, gluci-num, cerium, uranium and zinc and oxids of these elements 9. The process of producing aldehydes which comprises acting gases containing carbonmonoxide on a carboxylic acid ata temperature ranging between 200 and 500 C.

and in the presence v0f; a hydrogenating catalyst comprising chromium, iron andceriumi In testimony whereof I. havehereuntoset my hand. I

AD-OLIIF TOHAKNSEN. 

